William sawyer



UNITED STATES PATENT Orricn.

WILLIAM SAWYER, OF NEW YORK, N. Y., ASSIGNOR TO THE EASTERN ELEC- TRIC MANUFACTURING COMPANY, OF MIDDLETOWN, CONN.

ELECTRIC LAMP.

SPECIFICATION forming part of Letters Patent No. 227,388, dated May 11, 1880.

Application filed January 17, 1880.

To all whom it may concern:

Be it known that I, WILLIAM SAWYER, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Electric Lamps, of which the following is a full, clear, and exact description.

My invention relates to that method of elec- 1o tric lighting in which a pencil of carbon hermetically sealed in a glass globe charged with nitrogen gas is rendered incandescent by the passage of the electric current, and is more particularly an improvement upon the electric lamp invention of Mr. W. E. Sawyer, Letters Patent of the United States No. 219,771, dated September 16, 187 9; and it consists, especially, in the devices and means used to introduce the nitrogen gas into the globeand to close the opening through which the gas has been introduced after all air has been removed.

The methods of making the lamp air-tight are fully set forth in other applications, and I have therefore not included the same in the present specification.

To charge the lamp with nitrogen I employ the devices shown in the drawing, in which the bottom of the cup is represented by A. Through the aperture in the bottom a metal 0 plug, E, to which is attached a flexible Wire, F, is pushed aside by the compound tube B C C, the joint being made tight by the softrubber casing D. By means of the connection of the flexible tube H with the gasometer (not shown) the nitrogen passes upward to the top of the lamp through the long tube B, as indicated by the arrows, thus displacing the air, which finds its exit by way of the outer tube, C, which, in turn, is connected, by means of the flexible tube G, with the tube B of the next lamp, and thereby any number of lamps may be placed in. circuit and charged simultaneously. When, finally, the lamp is charged to a sufficient degree of purity, l withdraw the compound tube, still permitting the nitrogen to flow until the upper end of the tube has passed below the upper surface of the base A. I then, by means of the .wire F, draw down the plug E, which has been ground into the aperture in the base, thus forcing the rubber casing D out of place and forming a tight joint.

Having thus fully described my invention, what I claim as such, and desire to secure by Letters Patent, is

1. In an electric lamp operating by incandescence, the compound tube 13 C C, c011- structed and operating substantially as shown and described.

2. The combination of a filling-tube, B C, with the elastic casing D, plug E, and wire F, substantially as shown and described.

- WM. SAWYER.

Witnesses:

WM. G. GoNKLiN, ADOLPH FRANKE. 

